Most Europeans are exposed to PM levels above the WHO standards. Photo: Ian Broyles CC BY-NC-SA

Long-term exposure to fine particulate matter (PM2.5) can trigger atherosclerosis, adverse birth outcomes and childhood respiratory diseases, according to a World Health Organization (WHO) review released on 31 January. It also suggests a possible link with neurodevelopment, cognitive function and diabetes, and strengthens the causal link between PM2.5 and cardiovascular and respiratory deaths.

Over 80 per cent of Europeans are exposed to particulate matter (PM) levels above the standards – known as Air Quality Guidelines (AQGs) – recommended by the WHO. On average this deprives each citizen of 8.6 months of life.

Recent studies show associations between PM2.5 and mortality at levels below the current AQG of 10 micrograms per cubic metre (µg/m3) annual mean and so the review recommends a revision of the AQGs for PM by 2015.

As the current limit value for PM2.5 in the EU’s Ambient Air Quality Directive is more than twice as high as the current WHO standard, the EU should tighten its air quality legislation. The directive sets a limit value of 25 µg/m3 to be met by 2015 and it also contains an indicative limit value of 20 µg/m3 from 2020, subject to a review in 2013. Regarding PM10, the EU should maintain or possibly tighten its existing limit values.

The WHO review found new evidence for effects of long-term exposures to ozone (O3) on respiratory mortality and on deaths among persons with predisposing chronic conditions. This adds to previous findings on short-term effects, which are the focus of current regulation. An impact of ozone exposure on cognitive development and reproductive health, including pre-term birth is also suggested. The review recommends that the WHO should develop AQGs for long-term average ozone concentrations and that the EU considers setting a long-term target value.

New studies have associated short- and long-term exposure to nitrogen dioxide (NO2) with mortality, hospital admissions, and respiratory symptoms at concentrations at or below the current EU limit values (which are set at the same level as the AQGs). An update of the AQGs is therefore recommended, and dependent on the outcome of such an update the EU should consider revising the NO2 limit values.

The WHO-led project “Review of evidence on health aspects of air pollution – REVIHAAP” was commissioned within the framework of the 2013 review of the European Union’s air policy. A full technical report from the project will be available in the spring 2013. WHO Regional Director for Europe Zsuzsanna Jakab said: “We are confident that this new knowledge will ultimately lead to more stringent air pollution control policies to protect the health of European citizens”.

Christer Ågren

Report: “Review of evidence on health aspects of air pollution – REVIHAAP Project” – First results[2].

A global review of the burden of disease, published on 14 December, points to outdoor air quality as a top-level risk for public health. The study shows exposure to air pollution as one of the top ten risk factors for health globally. It is ranked 11th for countries in Western Europe, 14th for Central Europe and 15th for Eastern Europe.

“Everyday exposure to outside air pollution in Europe is now recognised as one of the big factors affecting our health,” said Anne Stauffer of the Health and Environment Alliance (HEAL). “For the first time, the Global Burden of Disease assessment has ranked an environmental factor among the more widely discussed ‘lifestyle’ risk factors, such as tobacco and alcohol.”

The analysis shows over 430,000 premature deaths and over 7 million years of healthy life lost in Western, Central and Eastern Europe in 2010 from exposure to fine particulate matter (PM2.5), with 166,000 premature deaths in Western Europe, 95,000 deaths in Central Europe, and 169,000 deaths in Eastern Europe, which includes Russia.